Northern Light
Superstar
But only if they were unbelievably dumb enough to be aiming themselves along a track with a tree close enough to hit in the first place.
In fairness, loss of control is a thing, and some saucers/sleds etc do go sideways or angled, sometimes kids also fall off and roll in a different direction at speed.
Its also not uncommon to underestimate how far a sled can go in certain conditions, if you get up to a good speed, on a steep incline you can keep going, at speed for upwards of 50M from the bottom of the hill, many people find that out the hard way.
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To be clear, I favour fewer rules, more permissions and accepting greater risk; but while I think the City can engage in grossly excessive risk management, I do understand that some serious injuries do happen, some a result of stupidity, some not, either way, good to mitigate the risk of the worst outcomes, where practical.